基于流式细胞仪分析超声造影剂包膜特性的实验研究  

Microbubble shell characterization using flow cytometry

作　　者：齐水宝[1] 崔炜程[1] 屠娟[1] 陈伟中[1] 

机构地区：[1]南京大学物理学院声科学与工程系近代声学(教育部)重点实验室,南京210093

出　　处：《南京大学学报（自然科学版）》2011年第2期147-154,共8页Journal of Nanjing University（Natural Science）

基　　金：国家自然科学基金(10704037;10974093;11074123);教育部博士点(新教师)基金(20070284070)

摘　　要：超声造影剂是由薄膜层包裹气体形成的微米量级的包膜气泡.随着医学超声技术的发展,超声造影剂在诊断及治疗超声领域的应用得到了广泛的关注.超声造影剂的包膜特性(如剪切模量及剪切粘度)是与其应用紧密相关的重要参数,对于决定气泡的许多功能特性都是非常重要的.本文在Mie散射理论基础上,利用进过改进的流式细胞仪测量了单个Definity(超声造影剂微泡的动力学行为,并对其包膜特性进行了分析.通过对实验测量得到的微泡动力学响应数据进行气泡动力学拟合来可以确定不同驱动声压(95-333 kPa之间)下造影剂微泡的包膜特性.结果显示:造影剂微泡包膜的剪切粘度随微泡平衡半径的增大而增大,随剪切速率的增大而减小;而包膜的弹性系数不随微泡的大小而变化.Experiments were performed to size and evaluate shell parameters for individual Definity ultrasound contrast microbubbles using a modified flow cytometer.Light scattering was modeled using Mie theory,and applied to calibration beads to calibrate the system.The size distribution and population were measured directly from the flow cytometer.The shell parameters(shear modulus and shear viscosity) were quantified at different acoustic pressures(from 95-333kPa) by fitting microbubble response data to a bubble dynamics model.The size distribution of Definity is consistent with manufacturer specifications.The shell shear viscosity increases with increasing equilibrium microbubble size,and decreases with increasing shear rate.The observed trends are independent of driving pressure amplitude.The shell elasticity does not vary with microbubble size.The results suggest that a modified flow cytometer can be an effective tool to characterize the physical properties of microbubbles,including size distribution,population,and shell parameters.

关 键 词：超声造影剂 流式细胞仪 驱动声压 MIE散射 

分 类 号：R445.1[医药卫生—影像医学与核医学]